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Nuclear Astrophysics in EURISOL. Carmen Angulo UCL, Louvain-la-Neuve and CARINA network www.cyc.ucl.ac.be/CARINA. In charge of the Subtask “Astrophysics” for EURISOL since January 2006. Understanding the Universe.

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Nuclear astrophysics in eurisol

Nuclear Astrophysics in EURISOL

Carmen Angulo

UCL, Louvain-la-Neuve and CARINA network

www.cyc.ucl.ac.be/CARINA

In charge of the Subtask “Astrophysics” for EURISOL since January 2006

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


Understanding the universe
Understanding the Universe

The structure and the evolution of stars are determined by precise laws and properties involving many aspects of physics

Hydrodynamic

Thermodynamic

Origin, Composition and Evolution of the Universe

Astronomy

Nuclear physics

Atomic physics

Cosmology

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


Hydrodynamic

Thermodynamic

Astronomy

Origin, composition and evolution of the Universe

Atomic physics

Cosmology

Masses

b-decay rates

n, e- and g interaction rates

Nuclear

Astrophysics

Nuclear Physics

Excited states properties

Fission barriers

Charged-particle and neutron induced

reaction rates

Synthesis of elements and energy production in stars

(Stability vs. Collapse)

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


Explaining the universe
Explaining the Universe

Long list of radioactive isotopes observed in the solar system

Explanation of detected amount: test of stellar models and nucleosynthesis calculations

Our current knowledge is very incomplete !

Figure from EURISOL report (based on Suess and Urey, Rev. Mod. Phys.,1956)

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


First carina workshop june 2005
First CARINA workshop (June 2005)

  • For a coherent program in nuclear astrophysics one needs:

    • High-intensity, high-purity light- to medium-mass radioactive beams.

    • Equipped with a full range of experimental tools:

      • Series of gas targets(recirculation for rare gases)

      • A multi-stage recoil separator

      • A high-resolution magnetic forward spectrometer

      • Large-area, fine-granularity solid-state detectors or telescopes(on sharing basis; standard electronics and DAQ systems)

      • A dedicated high-resolution, high-efficiency gamma-ray detection system

Find the final report at www.cyc.ucl.ac.be/CARINA

Main conclusion

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


Nuclear astrophysics in eurisol1
Nuclear astrophysics in EURISOL

  • Explosive scenarios: novae, X-ray burst, supernovae, neutron stars…

    The Hot CNO cycle and the rp process

    The r-process (the most challenging)

  • Moderate n-rich sites and AGB stars

    The s-process

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


Hot cno and rp process

27Si

28Si

27Al

24Al

25Al

26Al

rp-process

onset

21Mg

22Mg

23Mg

24Mg

25Mg

26Mg

23Na

20Na

21Na

22Na

NeNa

cycle

breakout

from HCNO

18Ne

19Ne

20Ne

21Ne

22Ne

17F

18F

19F

14O

15O

16O

17O

18O

HCNO

13N

14N

15N

13C

12C

Hot CNO and rp-process

25Al(p,g)26Si

26Al(p,g)27Si

25Si(a,p)28P

30P(p,g)31S

stable

unstable

19Ne(p,g)20Na

18Ne(a,p)21Na

18F(p,a)15O

15O(a,g)19Ne

14O(a,p)17F

End point of the rp-process:

Sn-Sb-Te region

(g,a), (p,g), b+

A < 106

Z

N

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


Novae and x ray bursters
Novae and X-ray bursters

Observables

  • Capture and transfer reactions rates on ‘short lived’ nuclei (N to Te)

  • Nuclear masses and p-separation energies (near the proton drip-line)

  • b-decay half-lives (including decay from excited and isomeric states)

Requirements

Specific cases:

Technical needs to be studied one-by-one

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


Targets
Targets

  • Inverse kinematics: proton- and alpha-rich targets

  • High intensity beams: need improved technologies

    • Extended-gas targets and gas cells

    • Jet-gas targets (specially suitable for recoil separators)

    • Cryogenic H and He targets

Detectors

  • Particles: DSSSD … large solid angles …

  • Gamma:

    • Large gamma arrays

    • Recoil separators (preferred)

No single solution for all cases !

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


18 f p a 15 o and nova gamma ray emission
18F(p,a)15O and nova gamma-ray emission

  • Gamma-ray emission from novae is dominated by positron annihilation following beta-decay of the newlysynthesized 18F

  • 18F (T1/2 = 110 min)  the annihilation radiation will be present after the expanding envelope of the novae becomes transparent.

  • Current and planned gamma-ray observatories  measurement of 18F abundances

  • Main destruction reaction: 18F(p,a)15O

     Need cross section values at c.m. energies of 200-300 keV

Snapshots of a Classical Nova Outburst (cortesy of J. José)

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


18 f p a 15 o a long standing problem
18F(p,a)15O: a long standing problem !

More than 10 years of research:

  • Direct measurement: 18F(p,a)15O – done (LLN, Oak Ridge, Argonne)

  • Elastic scattering: 18F(p,p)18F – done (LLN, Oak Ridge)

  • Transfer, DWBA: 18F(d,p)19F – done (LNN, Oak Ridge)

  • Inelastic scattering: 19Ne(p,p’)19Ne – done, last week at LLN

  • Elastic scattering: 15O(a,a)15O – accepted at LLN, next year

Beam (18F, 15O, 19Ne) intensities at LLN: 106 – 108 ions/s (0.1 – 10 pfA)

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


18 f p a 15 o present situation

  • Cross section is orders of magnitude lower:

  • Beam intensities required of the order of 1012 ions/s (0.2 pmA)

18F(p,a)15O: present situation

Rate at novae temperatures is still uncertain by orders of magnitude

Data from D. Bardayan et al. (Oak Ridge) and N. de Séréville et al. (LLN). Curves: R-matrix model

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


S and r processes
s- and r-processes

(p,g) and (a,g) reactions: inverse kinematics, low energy radioactive beams

Experimental data for (n,g) reactions are practically missing

  • Indirect methods?

  • Accuracy?  astrophysics models

  • Direct measurements:

  • neutron beams (n_TOF, FRANZ…)

  • implanted targets > 1016 atoms/cm2

    beams > 1010 ions/s (EURISOL?)

C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


The case of 60 fe
The case of 60Fe

  • Production of 60Fe (T1/2 ~ 106 yr) in massive stars (pre-supernovae) depends strongly on the very uncertain reactions:

    59Fe(n,g)60Fe

    60Fe(n,g)61Fe

    • Supernova output

    • Solar system formation triggered by a nearby supernova

  • The 60Fe isotope:

    • detected in deep sea sediments (Knie et al. 2004)

    • observed by INTEGRAL (Harris et al. 2005) – 60Co decay

  •  60Fe beam : EURISOL?

    C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


    Required beams
    Required beams

    Table from http://isolde.web.cern.ch/ISOLDE/

    Required intensities: 1010 – 1012 ions/s (~ ppA – pmA)

    C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


    The case of 107 pd
    The case of 107Pd

    • Spectroscopy observation of elements on the surface of very old metal-poor halo stars (early Universe) – Sneden et al. 2005

      • Above barium (A > 138), agreement with solar r-process pattern: early robust r-process ?

      • Below barium, disagreement, underproduction compared to solar system: a second r-process ?

         Ag abundance, specially low

    Mode 1: 107Ag(n,g)108Ag and 109Ag(n,g)110Ag are known

    Mode 2: 107Pd (b-) 107Ag, T1/2 = 6 106 yr

    But 107Pd(n,g)108Pd not known

    Implanted 107Pd target at EURISOL?

    C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


    The r process path
    The r-process path

    Physics case

    • Nuclear structure properties of n-rich nuclei of paramount importance for understanding and modelling of the r-process

    Proposed experiments

    Does such a research program sound realistic to you?

    • Systematic study of nuclear structure of neutron-rich nuclei between N=50 and N=82: possible all elements from Fe to Sn, covering all “waiting points” !

    Observables

    • Masses, half-lives, and possibly energies and spins of excited states, g.s. deformation, neutron capture rates… of about 150 nuclei

    Requirements

    • Low-energy intense beams

    • Penning trap mass spectrometer (masses)

    • Laser ion source (half-lives)

    C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


    Requirements for na community at eurisol
    Requirements for NA Community at EURISOL

    EURISOL cater to a broad range of physics interests

    How much beam time can be devoted to nuclear astrophysics

    experiments (very time-consuming)?

    Yes, if dedicated LE accelerator and target-ion-source

     see talk by Nigel Orr

    C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


    Call for ideas for fp7
    Call for Ideas for FP7

    • From a network to Joint Research Projects for NA

       For details, please, check the CARINA website: www.cyc.ucl.ac.be/CARINA

    • Ideas to be discussed in the next CARINA workshop: Spring 2007 in Belgium

      (exact dates and venue to be announced soon)

    C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


    Thanks to
    Thanks to:

    Maurizio Busso (Univ. Perugia)

    Alain Coc (CSNSM Orsay)

    Tom Davinson (Univ. Edinburgh)

    Jordi José (IEEC Barcelona)

    Gabriel Martinez-Pinedo (GSI Darmstadt)

    Alex Murphy (Univ. Edinburgh)

    Brian Fulton (Univ. York)

    Franz Käppeler (FZ Karlsruhe)

    Michael Heil (GSI Darmstadt)

    Alberto Mengoni (IAEA Vienna)

    Nigel Orr (LPC Caen)

    Endre Somorjai (ATOMKI Debrecen)

    Klaus Suemmerer (GSI Darmstadt)

    For some of the cases discussed here: references are in the EURISOL report

    C. Angulo, subtask “Astrophysics”, EURISOL Week, CERN, 27 – 30/11/2006


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